Primary open angle glaucoma is almost certainly a result of changes in the metabolism of trabecular meshwork. The importance of defining the normal and abnormal biochemistry of this tissue was specifically acknowledged in recommendations #13 and #17 in the 1977 Report of the Glaucoma Panel of the National Advisory Eye Council. Because of the great difficulty of studying the biochemistry of primate trabecular meshwork, we proposes to use the calf meshwork as our model system. Once the biochemical questions are clearly defined, using the plentiful calf tissue, the problem of learning something of the biochemistry of excised human trabecular meshwork can be more realistically addressed. Specifically we aim to do the following: To characterize the rate controlling enzymes of glycolysis, the pentose pathway, oxidative metabolism, and glycosaminoglycan biosynthesis; to identify and quantitate acid and alkaline phosphatase, hyaluronidase, and other lysosomal-type enzymes; to charactrize cAMP-sensitive protein kinase; and to develop a method of making an intact cell suspension of calf trabecular meshwork. We also plan to establish informal collaborative studies in which we will supply preparations of calf trabecular meshwork to other laboratories. Trabecular meshwork is readily dissected from calf eyes, yielding 250-340 mg of tissue in less than one hour. The dissection of human meshwork will be based on the method developed by Dr. Polansky. Enzyme activities and substrate levels are estimated by standard methods. In the second year of this project, we will scale down these procedures for human studies.